Abstract: The third layer of the Open System Interconnect (OSI) reference model is the Network Layer. The Network layer handles traffic, addressing and accounting. The network Layer controls the operation of the subnet, deciding which physical path the data should take based on the network conditions, priority of service and other factors. It translates logical addresses, or names into physical address. A router is a layer 3 device and is a networking device that forwards data packets between computer networks. A network is configured with routing protocols- static or dynamic routing because these routing protocols define/specify how the communication packets are forwarded and the route selection process (optimum route selection). In this paper we have considered a network topology in which a certain part of the network is configured with OSPF protocol and enclosed within area 0 and the other part, with routers configured with RIP, version 2. Route redistribution is carried out at the boundary routers of the two sections of the network. Since, OSPF and RIP v2 are entirely different routing protocols; route redistribution is done on the boundary routers belonging to both the sections. Route redistribution [1] allows routes from one routing protocol to be advertised into another routing protocol. Finally, in this paper we configure Access Control List (ACL) on the network. ACL also called Access-List can be configured for all routed network protocols to filter the packets of those protocols as the packets pass through a router. Main function of ACL is to filter network traffic by controlling whether router packets are forwarded or blocked at the routerís interfaces and also provide security in the network on which it is configured.

Keywords: Open System Interconnect (OSI) reference model, traffic, addressing and accounting, Access Control List (ACL), packets are forwarded or blocked at the routerís interfaces and also provide security in the network.